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Mad Cow Disease May Be Transmitted Before Symptoms Appear



The researchers say that developing a test to diagnose mad cow disease is among the most important steps in combating the disorder. In the early 1980s, when little was known about the cause and transmission of AIDS, the world's blood supply was unprotected against HIV, and some people developed the disease from transfusions with infected blood. Now tests are run to screen blood for HIV, but screening of donors is the primary way the blood supply is guarded today.


Brown calls the association between HIV and mad cow "unwise," saying the two diseases "are so different." But Bostock acknowledges that the situation is similar to the days when no tests were available to detect HIV in the blood supply. Even today, with advanced testing available to detect HIV, there is a two-week window between the time a person is infected with HIV and when the disease can be detected in the blood.


Brown tells WebMD he believes the U.S. will be spared outbreaks of mad cow disease. "There are lots of embargoes and lots of prevention. I think we have escaped and will continue to escape."

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